An artist's concept of a nova explosion (Credit: Public Domain)

Here is some exciting news for those who missed the solar eclipse on April 8, 2024. Between now and September, NASA predicts an even rarer celestial event — a nova outburst. Unlike the eclipse, this phenomenon can be observed from anywhere on Earth without using any special equipment.

What is a nova?

A nova only occurs in a star binary system with a red giant and white dwarf (Credit: NASA/ Public Domain)

A nova only occurs in binary star systems consisting of a "dying" star, typically a large red giant, and a "dead" star, also known as a white dwarf. Since the two stars orbit in sync, material shed by the red giant accumulates on the surface of the white dwarf. Eventually, the gathered material explodes in a burst of energy known as a nova. It results in a sudden and dramatic increase in brightness, illuminating the night skies. Usually, these events only be seen through a powerful telescope. But the upcoming T Coronae Borealis nova eruption will be visible with the unaided eye!

What is T Coronae Borealis?

T Coronae Borealis (T CrB) lies 3,000 light-years away from Earth (Credit: PopePompus/CC-BY-SA-4.0/ Wikimedia Commons)

T Coronae Borealis (T CrB) is a binary star system located 3,000 light-years away from Earth. It is well-known for its periodic nova outbursts. They occur approximately once in every 80 years. The last one was in 1946.

The recurring outbursts stem from the tight orbits of the system's red giant and white dwarf star. As the red giant heats up, it sheds its outer layers onto the surface of the white dwarf. This in turn, causes the white dwarf's atmosphere to heat up and eventually erupt. The explosion is bright enough to be seen from Earth. Remarkably, T CrB's white dwarf survives each nova event, only to experience it again in the future.

"As matter accumulates on the surface of the white dwarf, it heats up and you get higher and higher pressure until bang — it’s a runaway reaction," says Bradley Schaefer, an astrophysicist at Louisiana State University.

When will the explosion occur?

NASA expects the nova explosion to occur sometime before September 2024. But its exact timing is hard to determine.

“It could maybe even happen tonight,” says Schaefer. "More probably, it’ll be within the next couple of months, and very probably before the end of summer."

However, everyone will get a chance to see the rare phenomenon. That is because unlike the eclipse, the nova outburst will be visible to the unaided eye for several days and just over a week with binoculars. It will look like a bright star in the northern sky.